Google's machine translation is a useful starting point for translations, but translators must revise errors as necessary and confirm that the translation is accurate, rather than simply copy-pasting machine-translated text into the English Wikipedia.

Do not translate text that appears unreliable or low-quality. If possible, verify the text with references provided in the foreign-language article.

The Migration Period may be divided into two phases. The first phase, occurring between AD 300 and 500, is partly documented by Greek and Latin historians but difficult to verify archaeologically. It put Germanic peoples in control of most areas of the then-Western Roman Empire.[8] The Tervingi entered Roman territory (after a clash with the Huns) in 376. Some time thereafter in Marcianopolis, the escort to Fritigern (their leader) was killed while meeting with Lupicinus.[9] The Tervingi rebelled, and the Visigoths, a group derived either from the Tervingi or from a fusion of mainly Gothic groups, eventually invaded Italy and sacked Rome in 410, before settling in Iberia and founding a kingdom that lasted for 300 years. They were followed into Roman territory by the Ostrogoths, led by Theodoric the Great, who settled in Italy. In Gaul the Franks (a fusion of western Germanic tribes whose leaders had been aligned with Rome since the third century AD) entered Roman lands gradually and peacefully during the fifth century, and were accepted as rulers by the Roman-Gaulish population. Fending off challenges from the Allemanni, Burgundians, and Visigoths, the Frankish kingdom became the nucleus of the future France and Germany. The initial Anglo-Saxon settlement of Britain occurred during the fifth century, when Roman control of Britain had come to an end.[10]

A number of contemporary historical references worldwide refer to an extended period of extreme weather during 535–536. Evidence of this cold period is also found in dendrochronology and ice cores. The consequences of this cold period are debated.

The analysis of barbarian identity and how it was created and expressed during the Migration Age has elicited discussion among scholars. Herwig Wolfram (a historian of the Goths),[12] in discussing the equation of migratio gentium with Völkerwanderung, observes that Michael Schmidt introduced the equation in his 1778 history of the Germans. Wolfram observed that the significance of gens as a biological community was shifting even during the early Middle Ages; "to complicate matters, we have no way of devising a terminology that is not derived from the concept of nationhood created during the French Revolution".

The "primordialistic"[13] paradigm prevailed during the 19th century. Scholars such as German linguist Johann Gottfried Herder viewed tribes as coherent biological (racial) entities, using the term to refer to discrete ethnic groups.[14] He believed that the Volk were an organic whole, with a core identity and spirit evident in art, literature and language. These were seen as intrinsic characteristics unaffected by external influences, even conquest.[15] Language, in particular, was seen as the most important expression of ethnicity. They argued that groups sharing the same (or similar) language possessed a common identity and ancestry.[16] The Romantic ideal that there had once been a single German, Celtic or Slavic people who originated from a common homeland and spoke a common tongue helped provide a conceptual framework for political movements of the 18th and 19th centuries such as Pan-Germanism and Pan-Slavism.[15]

Beginning in the 1960s a reinterpretation of archaeological and historic evidence prompted scholars (such as Goffart and Todd) to propose new models for explaining the construction of barbarian identity, maintaining that no sense of shared identity was perceived by the Germani;[17][18][19] a similar theory has been proposed for Celtic and Slavic groups.[20] This theory states that the primordialist mode of thinking was encouraged by a prima facie interpretation of Graeco-Roman sources, which grouped together many tribes under such labels as Germani, Keltoi or Sclavenoi (encouraging their perception as distinct peoples). Modernists argue that the uniqueness perceived by specific groups was based on common political and economic interests, rather than biological or racial distinctions.

The role of language in constructing and maintaining group identity can be ephemeral, since large-scale language shifts occur commonly in history.[21] Modernists propose the idea of "imagined communities"; the barbarian polities in late antiquity were social constructs, rather than changeless lines of blood kinship.[22] The process of forming tribal units was called "ethnogenesis", a term coined by Soviet scholar Julian Bromley.[23] The Austrian school (led by Reinhard Wenskus) popularized this idea, which influenced medievalists such as Herwig Wolfram, Walter Pohl and Patrick Geary.[17] It argues that the stimulus for forming tribal polities was perpetuated by a small nucleus of people, known as the Traditionskern ("kernel of tradition"), who were a military or aristocratic elite. This core group formed a standard for larger units, gathering adherents by employing amalgamative metaphors such as kinship and aboriginal commonality and claiming that they perpetuated an ancient, divinely-sanctioned lineage.[24]

A capable soldier would be able to assume the group identity without being born into the "tribe". "A victorious campaign confirmed [the leaders'] right to rule and drew [to] them an ever-growing people who accepted and shared in their identity".[24] In time, these heterogeneous armies grew into a new people possessing "a strong belief in a common biological origin".[25] Halsall argues that no objectively-definable criterion can be consistently used to distinguish ethnic groups from one another: language, social customs, geographic habitation, religion or a common origin. "The only common factor in defining ethnicity is belief: in the reality of your group and the difference to others".[26]

Walter Pohl highlights the dynamic nature of group identity, proposing that during the Migration Period people could live in circumstances of "ethnic ambiguity". Given that ethnicity was important for the upper classes, they could adopt multiple ethnicities to secure the allegiance of their partners and followers: a phenomenon referred to as "situational ethnicity".[26] To advance socially, one needed to "grow into a dominating group with high prestige, to copy its lifestyle".[27] The process of assimilation could produce "a wide variety of transitional stages".[28] Followers could also disband from larger units. Factions arose, challenging the right to lead the people and uphold their traditions. Conversely defeat by an external power could mean the end of a ruler and his people, who were absorbed into the victorious confederacy.[29] "Seen in this light, 'ethnic' identity among barbarians was extraordinarily fluid, as new groups emerged and old ones disappeared".

Peter Heather suggests that constructionism and modernism represent two extremes of the spectrum of possibilities. The process of assimilation and appropriation of new group identity varied from group to group. He alludes to literary sources, which describe two contrasting models of interaction: the Sclavenes were prepared (after a given period) to accept prisoners as full and free members of their tribal groups; on the other hand, the Huns (although incorporating non-Hun groups) kept them separate and subordinate. Rather than being aristocratic kernels, he argues that the identity of tribal groups was maintained by a contingent of "notables" and freemen. He clarifies that while groups like the Goths were multi-ethnic, full assimilation was not the rule.[30] He proposes that conquered groups held a subordinate status either as otherwise-autonomous tribute-payers or as disadvantaged strata within mixed settlements. Even when a homogeneous material culture arose, disparate groups were likely to preserve their unique identity and language.[31]

Whatever the case, this process of building large-scale group identity was particularly evident along the Roman frontier, prompted by the example of Roman provincial life and the threat of Roman attack.[32] Ethnicity was a complex, subjective and multi-layered process, and the Migration Period saw groups rise and fall. Confederations like the Huns and the Vandals arose, to vanish abruptly within a few generations. Other, previously-obscure groups (like the Angles and the Franks) created enduring polities. Even ancient groups like the Goths (who existed from late antiquity until the Middle Ages) underwent profound transformation. Given constant migrations, changing allegiances, and new cultural appropriations, all that remained constant was their Gothic name.[33] As Thomas Noble states, "tribes are no longer imagined to have been "marching for centuries at a time in ordered ranks with homogeneous ethnic compositions" from a distant, localized homeland across Europe into a settlement on Roman soil:

"The common, track-filled map of the Völkerwanderung may illustrate such [a] course of events, but it misleads. Unfolded over long periods of time, the changes of position that took place were necessarily irregular ... (with) periods of emphatic discontinuity. For decades and possibly centuries, the tradition bearers idled, and the tradition itself hibernated. There was ample time for forgetfulness to do its work".[34]

Historians have postulated several explanations for the appearance of "barbarians" on the Roman frontier: weather and crops, population pressure, a "primeval urge" to push into the Mediterranean, or the "domino effect" (whereby the Huns fell upon the Goths who, in turn, pushed other Germanic tribes before them). Entire barbarian tribes (or nations) flooded into Roman provinces,[citation needed] ending classical urbanism and beginning new types of rural settlements.[35] In general, French and Italian scholars have tended to view this as a catastrophic event: the destruction of a civilization and the beginning of a "Dark Age" which set Europe back a millennium.[35] In contrast, German and English historians have tended to see it as the replacement of a "tired, effete and decadent Mediterranean civilization" with a "more virile, martial, Nordic one".[35] Rather than "invasion", German and Slavic scholars use the term "migration" (German: Völkerwanderung, Czech: Stěhování národů, Swedish: folkvandring and Hungarian: népvándorlás), aspiring to the idea of a dynamic and "wandering Indo-Germanic people".[36]

The scholar Guy Halsall has seen the barbarian movement as the result of the fall of the Roman Empire, not as its cause.[35] Archaeological finds have confirmed that Germanic and Slavic tribes were settled agriculturalists[37] who were probably merely "drawn into the politics of an empire already falling apart for quite a few other causes". The Crisis of the Third Century caused significant changes within the Roman Empire, in both its western and eastern portions.[38] In particular, economic fragmentation removed many of the political, cultural and economic forces which had held the empire together.[39] The rural population in Roman provinces became distanced from the metropolis, and there was little to differentiate them from other peasants across the Roman frontier. In addition, Rome increasingly used foreign mercenaries to defend itself. This "barbarisation" of the Empire was paralleled by changes within barbaricum. For example, the Roman Empire played a vital role in building up barbarian groups along its frontier. Propped up with imperial support and gifts, the armies of allied barbarian chieftains served as buffers against hostile barbarian groups. The disintegration of Roman economic power weakened groups that had come to depend on Roman gifts for the maintenance of their own power. With the arrival of the Huns, this prompted many groups to invade the provinces for economic reasons.[40]

The nature of the barbarian takeover of former Roman provinces varied from region to region. For example, in Aquitaine the provincial administration was largely self-reliant. Halsall has argued that local rulers simply "handed over" military rule to the Ostrogoths, acquiring the identity of the newcomers.[8] In Gaul the collapse of imperial rule resulted in anarchy: the Franks and Alemanni were pulled into the ensuing "power vacuum",[41] resulting in conflict. In Spain local aristocrats maintained independent rule for some time, raising their own armies against the Vandals. Meanwhile, the Roman withdrawal from lowland England resulted in conflict between Saxons and the Brythonic chieftains (whose centres of power retreated westward as a result). The Eastern Roman Empire attempted to maintain control of the Balkan provinces, despite a thinly-spread imperial army that relied mainly on local militias and an extensive effort to re-fortify the Danubian limes. The ambitious fortification efforts collapsed, worsening the impoverished conditions of the local populace and resulting in colonization by Slavic warriors and their families.[42]

Halsall and Noble have argued that such changes stemmed from the breakdown in Roman political control, which exposed the weakness of local Roman rule. Instead of large-scale migrations, there were military takeovers by small groups of warriors and their families (who usually numbered in the tens of thousands). This process involved active, conscious decision-making by Roman provincial populations. The collapse of centralized control severely weakened the sense of Roman identity in the provinces, which may explain why the provinces underwent dramatic cultural changes at this time even though few barbarians settled in them.[43] Ultimately, the Germanic groups in the Western Roman Empire were accommodated without "dispossessing or overturning indigenous society" and maintained a structured and hierarchical (albeit attenuated) form of Roman administration.[44] Ironically, they lost their unique identity as a result of this accommodation and were absorbed into Latinhood. In contrast, in the east, Slavic tribes maintained a more "spartan and egalitarian"[45] existence bound to the land "even in times when they took their part in plundering Roman provinces".[46] Their organizational models were not Roman, and their leaders were not normally dependent on Roman gold for success. Thus, they arguably had a greater effect on their region than the Goths, Franks or Saxons had on theirs.[47]

Based on the belief that particular types of artifacts (generally elements of personal adornment found in a funerary context) are thought to indicate the race and/or ethnicity of the person buried, the "Culture-History" school of archaeology assumed that archaeological cultures represent the Urheimat (homeland) of tribal polities named in historical sources.[48] As a consequence, the shifting extensions of material cultures were interpreted as the expansion of peoples.[49] Influenced by constructionism, process-driven archaeologists rejected the Culture-Historical doctrine;[49] they marginalized the discussion of ethnicity altogether, and focused on the intragroup dynamics which generated such material remains. Moreover, they argued that adoption of new cultures could occur through trade or internal political developments rather than military takeovers.

Many scholars take a more moderate position. While recognizing that artifacts do not possess an inherent "ethnic ascription", some artifacts may have been used as "emblems in identity and otherness – of belonging and exclusions".[50] Peter Heather suggests that although shifts in culture should not solely rely on migratory explanations, there is no reason to a priori rule them out (especially if there is evidence from literary sources).[51] Profound changes in culture (and language) could occur through the influx of a ruling elite with minimal (or no) impact on overall population composition,[52] especially if it occurs when the indigenous population is receptive to such changes.

^Anthony D. Smith, The Ethnic Origins of Nations (Oxford, 1966) pp. 6ff, coined the term to separate these thinkers from those who view ethnicity as a situational construct, the product of history, rather than a cause, influenced by a variety of political, economic, and cultural factors.

^This was influenced by the 'family tree' model (Stammbaun) of linguistics, in that relationships between related languages being the result derivation from a common ancestor. This model still is very influential in linguistics

^Curta (2001) [T]he archaeological evidence of late fourth- and fifth-century barbarian graves between the Rhine and Loire suggests that a process of small-scale cultural and demographic change took place on both sides of the Roman frontier. Can we envisage Roman-Slavic relations in a similar way?